1. Field of the Invention
The present invention relates to a lock, which is comprised of inner and outer locking elements respectively fitted to inner and outer sides of a door so that people inside the room also have to use the key to unlock the door after the door is locked, more particularly one, which is secured to the door in such a manner that none of the screws show that are used to fasten the lock to the door, preventing thieves from easily damaging, dismantling or removing the lock to open the door.
2. Brief Description of the Prior Art
Conventional door locks are comprised of a locking element on an outer side of the door, and a knob on an inner side of the door so that after the door is locked, people outside the house cannot open the door without the key while people inside the house can open the door without the key. Such locks are not ideal because thieves can open the door to easily steal after they have entered the house from windows stealthily. Therefore, bi-directional locks are provided to overcome the above disadvantages, which locks are made such that people inside the room also have to use the key to open the door after the door is locked.
Referring to FIG. 6, a conventional bi-directional lock is provided, which is comprised of inner and outer locking elements 10, 20 secured to inner and outer sides of a door 30 so that people inside the house also has have to use the key to unlock the door 30 after the door 30 is locked with the lock; screws 40 are screwed through the inner locking element 10, and the door 30, and then screwed into the outer locking element 20. Thus, a person in the house without the key can""t operate the inner locking elements 10 to unlock the door in case the door has been locked by means of operating the outer locking element 20 with the key.
The above lock is easy to damage or dismantle because the screws 40 show on the inner side of the door, and can be easily screwed off the lock. Therefore, thieves can easily unlock, and open the door 30 after they have entered the room stealthily. Consequently, thieves can leave the house through the door, making it difficult for other people to suspect that thieves are stealing, and can easily steal large properties from the house by moving them via the door.
It is a main object of the present invention to provide a bi-directional lock to a house so that people inside the house also have to use the key to unlock the door after the door is locked, and which lock is secured to the door in such a manner that none of the fixing elements show that are used to fasten the lock to the door, preventing thieves from easily removing the lock from the door to open the door.
The lock is comprised of inner and outer locking elements respectively disposed on inner and outer sides of a door; the outer locking element has several hollow posts, which project into the door and don""t communicate with outside, and into which screws are screwed from the inner side of the door; the inner locking element has several fixing posts, which project into the door, and into which screws are screwed from the free end of the door where the dead bolt is disposed.